From politics to Facebook, transparency is on all our minds. And science, of
course, depends on transparency to advance.
A big barrier to transparency in scientific research is the cost of viewing
peer reviewed articles. A simple Google® Scholar search on a topic of your
choosing will result in thousands of articles, many of which you might want to
read. Unfortunately, to review an article requires payment of $30 or more. Who
can afford that?
The mission of open access sites like PLOS-Public Library of Science (http://journals.plos.org/) is to breach the cost barrier and promote the free flow of peer reviewed
research.
Granted, the focus of PLOS seems to be on medical research. And yet, even so,
an article by ExxonMobil researchers Prosset and Hedgpeth, is a part of the
trove of treasures in this collection.
Viva transparency!
///////
Effects of
bioturbation on environmental DNA migration through soil media
Christopher M. Prosser
& Bryan M. Hedgpeth
PLOS Published: April 24, 2018 •
https://doi.org/10.1371/journal.pone.0196430
Contributed equally to this work with: Christopher M. Prosser, Bryan M.
Hedgpeth
Roles: Conceptualization, Methodology, Writing
* E-mail: Christopher.m.prosser@exxonmobil.com
ORCID: http://orcid.org/0000-0002-5209-1878 Bryan M. Hedgpeth
Affiliation: ExxonMobil Biomedical Sciences
Incorporated, Annandale, NJ, United States of America
Abstract
Extracting and identifying genetic material from environmental media (i.e.
water and soil) presents a unique opportunity for researchers to assess biotic
diversity and ecosystem health with increased speed and decreased cost as
compared to traditional methods (e.g. trapping). The heterogeneity of soil
mineralogy, spatial and temporal variations however present unique challenges
to sampling and interpreting results. Specifically, fate/transport of genetic
material in the terrestrial environment represents a substantial data gap. Here
we investigate to what degree, benthic fauna transport genetic material through
soil. Using the red worm (Eisenia fetida), we investigate how natural movement
through artificial soil affect the transport of genetic material. All
experiments were run in Frabill® Habitat® II worm systems with approximately 5
cm depth of artificial soil. We selected an ªexoticº source of DNA not expected
to be present in soil, zebrafish (Danio rerio) tissue. Experiment groups
contained homogenized zebrafish tissue placed in a defined location combined
with a varying number of worms (10, 30 or 50 worms per experimental group).
Experimental groups comprised two controls and three treatment groups
(representing different worm biomass) in triplicate. A total of 210 soil
samples were randomly collected over the course of 15 days to investigate the
degree of genetic transfer, and the rate of detection. Positive detections were
identified in 14% - 38% of samples across treatment groups, with an overall
detection rate of 25%. These findings highlight two important issues when
utilizing environmental DNA for biologic assessments. First, benthic fauna are
capable of redistributing genetic material through a soil matrix. Second,
despite a defined sample container and abundance of worm biomass, as many as
86% of the samples were negative. This has substantial implications for
researchers and managers who wish to interpret environmental DNA results from
terrestrial systems. Studies such as these will aid in future study protocol
design and sample collection methodology. Introduction Accurate biodiversity
assessments are a central component to compliance with environmental regulations.
In the United States, for example, environmental impact statements under the National
Environmental Policy Act require extensive baseline information on
biodiversity. Similarly, quantitative biodiversity assessments are important
for assessing the progress of habitat reclamation efforts. However, traditional
biodiversity monitoring relies on direct (ex. traps, sightings) or indirect
(ex. tracks, calls) observation of organisms. Especially true for direct
methods such as trapping or netting, these activities are often time consuming,
expensive, and impractical in remote or hard to reach regions. Over the past
decade, technological advances have resulted in the ability to detect the
presence of organisms through amplification of environmental DNA (eDNA). eDNA is
a generic term collectively referring to all genetic material that can be
extracted from environmental media. Examples are extracellular DNA fragments,
hair, feces, blood, free microbial cells, pollen or any other source by which
cells and/or tissue may enter the environment [1]. Due to high precision, species-specific
detection and low rates of false positives, eDNA has been increasingly utilized
for an array of studies including biodiversity assessments, mapping of species
distributions, and detection of invasive and endangered species [1±5].
DNA-based ecosystem monitoring can have distinct advantages over traditional
sampling methods, including being less invasive/less destructive than
trapping/netting. Sampling only environmental media (water, soil, sediment),
reduces stress and danger of entrapment of valuable (e.g. endangered) species
in nets or snares. The DNA sequencing of bulk material containing the DNA of
dozens or hundreds of species would have been cost-prohibitive with older low
throughput DNA sequencing platforms (e.g. Sanger sequencing). However, with
next generation DNA sequencers (NGS), which use high-throughput technologies
such as massively parallel sequencing, it is now possible to generate millions
of DNA reads from bulk material in a short period of time [6]. Additionally, newer
DNA sequencing technologies boast low detection limits (10−8 ng/μL) allowing
for low levels of genetic material to be amplified and sequenced. To date, the
majority of eDNA studies have focused on aquatic and/or wetland systems [3, 7±9].
This is most likely due to methodological advantages of sampling aquatic media.
For example, lotic and lentic systems provide defined boundaries within which
to sample and relatively large volumes of water (as large as several liters)
can be filtered to concentrate available genetic material. In contrast to eDNA
analysis from aquatic/marine systems, there is generally a paucity of data from
terrestrial habitats. Soil matrices present unique challenges that are not encountered
in aquatic systems. For example, the volume of soil used in extractions is
typically a limiting factor (~0.25g soil per extraction). Additionally, little
is known on eDNA fate and mobility in terrestrial systems over time and space
(i.e. once deposited, there is little data to predict transport and/or
persistence). A non-detect may be a false-negative if in fact the complexity of
soil matrix precludes homogenous distribution of genetic material thus limiting
spatial area from which it can be detected. As compared to aqueous media, the
chemical complexity and reactivity of soils displays a greater degree of
spatial and temporal heterogeneity, raising questions about eDNA mobility in
soils. Soil mineralogy (e.g. clay, sand, silt) and subsequent mixtures (e.g.
silty clays) will greatly influence the amount of surface reactive particles
present, and thus the adsorption of genetic material within that matrix [10].
Physicochemical interactions influencing eDNA mobility within the soil matrix
are highly variable and will depend on DNA fragment size, soil mineralogy,
hydrophobicity, pH and ionic strength [11]. Persistence of eDNA in soils has
also received limited attention and is incompletely understood. The presence of
clay and soil colloids has been suggested to prohibit enzymatic degradation of
genetic material thus potentially prolonging its availability for detection
[12,13]. In anoxic environments, such as lake sediment, eDNA has been recovered
dating back thousands of years [14]. Conversely, eDNA can also be taken up by
bacteria as a source of nutrition expediting its removal from the environment [10].
Such uncertainties have led to wide estimates in persistence ranging from days
to years in the top 15 cm of soil [15]. To date, few field studies have been
conducted specifically focused on eDNA extraction from soil. However, in recent
years researchers have investigated soil samples from natural wetland habitats
[16] as well as in more spatially defined zoos and parks [17]. Fahner et al.
[16] investigated large-scale plant monitoring using DNA metabarcoding.
Researchers collected core samples from the Ramsar designated Peace-Athabasca
Delta in Wood Buffalo National Park, Alberta, Canada with the goal of
identifying standard DNA markers designed to evaluate floral biodiversity. An
important approach in this study was the targeting of full length amplicons (400±900
base pairs), demonstrating this length is not so extensively degraded to
preclude their use in biodiversity assessment. Andersen et al. [17]
investigated a fundamental relationship between known species abundance and
detectable levels of eDNA. Researchers isolated and amplified eDNA from known species
in safari parks, zoological gardens, and farms and found that detectable eDNA
generally reflected the diversity of animals on the landscape. However, these
researchers reported patchy detection (as low as 31%) from soil surface.
Researchers also reported eDNA extraction efficiency was inversely proportional
to organic carbon content of the soil. The vast majority of studies to date
have focused on the presence/absence of DNA in the environment; however, such
studies do little to investigate eDNA fate and transport. While there are some
exceptions in aquatic systems (i.e. [8]), there is a noticeable data gap investigating
such effects in terrestrial systems. While the deposition of genetic material
through normal processes (e.g. hair loss) is generally accepted, the degree to
which physical (e.g. wind/rain) and biological (bioturbation) processes
disseminate genetic material through terrestrial media are not well understood.
As eDNA continues to grow as a tool for use in ecological assessments, a
fundamental understanding of detection rate, and the risk of false negatives in
terrestrial media will bolster data interpretation. Given the paucity of data
related to eDNA fate and transport within terrestrial environments, the scope
of this study focused on whether bioturbation will transport eDNA through soil.
Our study was designed to investigate if normal biotic activity (e.g. the
natural movement of worms through soil) would transport detectable levels of
genetic material from a single, well defined depositional source, to adjacent
areas. The redworm (Eisenia fetida) was used in controlled laboratory
experiments to examine if, and to what degree bioturbation moves DNA from a
single deposition source through soil.
source: http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0196430
///////
Here are some excerpts from the PLOS Web site …
///////
Founded in 2001 as an alternative to the
growing constraints of traditional scientific publishing, the Public Library of
Science (PLOS) rapidly evolved into a driving force in the Open Access
movement.
source: https://www.plos.org/history
///////
Your Research, Our Resources
QUALITY Scientists that peer review and
serve on editorial boards for PLOS are experts committed to reporting, ethics
and publishing guidelines. This means every article published with PLOS is the
most robust it can be.
SPEED From submission to acceptance,
PLOS publishing processes are tightly focused to eliminate unnecessary
publication delays.
INFLUENCE Policymakers, educators,
journalists and organizations around the world turn to trustworthy research
published in PLOS journals. In 2017, nearly 4,000 research articles were
covered by news sources such as the BBC, NPR, The New York Times and The
Guardian. That's a 15% increase from our 2016 coverage.
OPEN ACCESS FOR MAXIMUM IMPACT PLOS
research attracts more than 15 million article views per month. Articles are
immediately and freely available under a Creative Commons Attribution License
(CC BY).
ARTICLE-LEVEL METRICS (ALMS) PubMed,
Scopus, Web of Science and Google Scholar feature PLOS articles. At PLOS, all
these sources feed into ALMs to help demonstrate the influence of your work.
DATA AVAILABLITY Authors commit to
making the data underlying their conclusions fully available, when at all
possible. This enables validation, replication and reproducibility—all
increasing the value of research. source: source: https://www.plos.org/why-publish-with-plos
///////
TIP:
Search the PLOS Web (http://journals.plos.org/plosone/)
using whatever term you are interested in … like, for example, desulfurization.
Then read to your heart’s content.
Showing posts with label open access. Show all posts
Showing posts with label open access. Show all posts
Wednesday, May 2, 2018
Thursday, February 5, 2015
Open Access Alert: Procedia
“Even the just
may sin with an open chest of gold
before them” -- Latin Proverb
Procedia encompasses a number of interesting open access sources. Many of them will interest anyone engaged in desulfurization research. As such, they are good for full text browsing. The easiest way to search for Procedia articles is to go to the ScienceDirect site (www.sciencedirect.com) and do an advanced search.
Here is a recent article …
///////
Comparison Between Alkylation and Transalkylation Reactions Using Ab Initio Approach
Procedia Chemistry 10 ( 2014 ) 430 – 436
2014 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/).
XV International Scientific Conference “Chemistry and Chemical Engineering in XXI century” dedicated to Professor L.P. Kulyov
By Asem Nurmakanova, Anastasiya Salischeva, Alyona Chudinova, Elena Ivashkina, & Anna Syskina
National Research Tomsk Polytechnic, University, Lenin Avenue, 30, Tomsk, 634050, Russian Federation
OJSC “Omsky Kauchuk”, prospekt Gubkina, 30, Omsk, 644035, Russian Federation
Abstract
This study concerns thermodynamic and kinetic regularities of benzene alkylation with propylene and diisopropylbenzene transalkylation by investigating reaction mechanism. For each step, thermodynamic parameters, such as pre - exponential factor and activation energy were determined. Ab initio approach was used for this purpose. Also effects of solvation and ions formation were taken into account. Finally, comparative analysis of two processes was made.
1. Introduction
1.1 Background
Cumene is an important raw material in petrochemistry to obtain phenol and its co - product – acetone . Usually cumene is produced at the same facility that manufactures phenol. Its synthesis is based on the alkylation of benzene with propylene using a с id catalysts. The main technology now used for cumene producing is a process catalyzed by phosphoric acid loaded on ceyssatite patented by the Universal Oil Products Company (UOP Co.). AlCl3 is also chosen as the catalyst. However, such materials usually introduce various problems such as corrosion, harmful effects on the environment . Some processers used BF3, but it had controlling difficulties in comparison with AlCl, and the BF3 process requires higher temperature and pressure to operate. Since 1965, acid zeolite is of great interest for cumene manufacture, but only recently it has been commercialized by Dow, Mobil, CD Tech, UOP and Enichem. Despite that, zeolite catalysts were widely used because of their safety, easy deactivation by coking, short regeneration cycle, and hard reaction condition became problems. A new type of catalyst for this process – ionic liquids – was developed, but is not commercialized . In spite of new catalysts emergence, process with aluminum chloride stays actual for many cumene producers. It is necessary to increase cumene production, because nowadays demand for cumene rose up to 12 million tons in 2011 and keeps growing.
1 .2 Reaction
The alkylation reaction of benzene with propylene is carried out in the presence of Lewis acids. It is known that alkylation occurs through activation of the olefin by catalyst, and then activated complex react s with benzene and alkylbenzenes.
Source: http://ac.els-cdn.com/S187661961400117X/1-s2.0-S187661961400117X-main.pdf?_tid=671789cc-a8b0-11e4-8ee1-00000aacb35e&acdnat=1422643812_65c2c345f702f7eeb47cc1e59aef483e
///////
TIP: Try the following search in ScienceDirect (www.sciencedirct.com) …
Elsevier ScienceDirect (www.sciencedirect.com) Advanced Search:
Journal Name: Procedia
Any field: Dibenzothiophene
Here are some of the results of the above search …
///////
Ionic Liquids: - The Novel Solvent for Removal of Dibenzothiophene from Liquid Fuel
Procedia Engineering, Volume 51, 2013, Pages 314-317
Composition of Initiated Cracking Products of High-sulfur Natural Bitumen
Procedia Chemistry, Volume 10, 2014, Pages 326-331
Deep Removal of Sulfur from Model Liquid Fuels using 1-Butyl-3-Methylimidazolium Chloride
Procedia Engineering, Volume 51, 2013, Pages 416-422
Sonocatalytic Oxidative Desulfurization of Thiophene and Its Derivatives
Procedia Engineering, Volume 42, 2012, Pages 1711-1719
Geochemistry of Aromatic Fractions in Es4 Oil Extracts from the South Slope of Dongying Sag and Its Implications
Procedia Environmental Sciences, Volume 11, Part B, 2011, Pages 680-685
The Biomarker Properties and Comparisons of Sahinali, Beypazarı and Karapınar (Turkey) Coaly Plio-Miocene Depositions
Energy Procedia, Volume 59, 2014, Pages 142-149
Heat Treatment Condition Influence on Novokuibyshevsk Vacuum Residue Component Composition
Procedia Chemistry, Volume 10, 2014, Pages 424-429
Recovery of Hazardous Metals from Spent Refinery Processing Solid Catalyst
Procedia Environmental Sciences, Volume 16, 2012, Pages 253-256
Enhanced Adsorption of Methyl Orange by Vermiculite Modified by Cetyltrimethylammonium Bromide (CTMAB)
Procedia Environmental Sciences, Volume 13, 2012, Pages 2179-2187
Air-Stable Anthracene-Phosphine Oxide Adduct Ligand in Pd Catalysed Suzuki-Miyaura Reactions
APCBEE Procedia, Volume 3, 2012, Pages 154-160
Biodegradation of Phthalate Esters by Variovorax sp
APCBEE Procedia, Volume 1, 2012, Pages 16-21
Analysis of Volatile Components from Dictyophora rubrovolota Zang, Ji Et Liou
Procedia Engineering, Volume 37, 2012, Pages 240-249
Cracking of Petroleum Residues by Reactive Molecular Distillation
Procedia Engineering, Volume 42, 2012, Pages 329-334
The Distribution of n-alkanes and polycyclic aromatic hydrocarbons in Water of Taihu Lake
Procedia Environmental Sciences, Volume 12, Part A, 2012, Pages 258-264
///////
Procedia encompasses a number of interesting open access sources. Many of them will interest anyone engaged in desulfurization research. As such, they are good for full text browsing. The easiest way to search for Procedia articles is to go to the ScienceDirect site (www.sciencedirect.com) and do an advanced search.
Here is a recent article …
///////
Comparison Between Alkylation and Transalkylation Reactions Using Ab Initio Approach
Procedia Chemistry 10 ( 2014 ) 430 – 436
2014 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/).
XV International Scientific Conference “Chemistry and Chemical Engineering in XXI century” dedicated to Professor L.P. Kulyov
By Asem Nurmakanova, Anastasiya Salischeva, Alyona Chudinova, Elena Ivashkina, & Anna Syskina
National Research Tomsk Polytechnic, University, Lenin Avenue, 30, Tomsk, 634050, Russian Federation
OJSC “Omsky Kauchuk”, prospekt Gubkina, 30, Omsk, 644035, Russian Federation
Abstract
This study concerns thermodynamic and kinetic regularities of benzene alkylation with propylene and diisopropylbenzene transalkylation by investigating reaction mechanism. For each step, thermodynamic parameters, such as pre - exponential factor and activation energy were determined. Ab initio approach was used for this purpose. Also effects of solvation and ions formation were taken into account. Finally, comparative analysis of two processes was made.
1. Introduction
1.1 Background
Cumene is an important raw material in petrochemistry to obtain phenol and its co - product – acetone . Usually cumene is produced at the same facility that manufactures phenol. Its synthesis is based on the alkylation of benzene with propylene using a с id catalysts. The main technology now used for cumene producing is a process catalyzed by phosphoric acid loaded on ceyssatite patented by the Universal Oil Products Company (UOP Co.). AlCl3 is also chosen as the catalyst. However, such materials usually introduce various problems such as corrosion, harmful effects on the environment . Some processers used BF3, but it had controlling difficulties in comparison with AlCl, and the BF3 process requires higher temperature and pressure to operate. Since 1965, acid zeolite is of great interest for cumene manufacture, but only recently it has been commercialized by Dow, Mobil, CD Tech, UOP and Enichem. Despite that, zeolite catalysts were widely used because of their safety, easy deactivation by coking, short regeneration cycle, and hard reaction condition became problems. A new type of catalyst for this process – ionic liquids – was developed, but is not commercialized . In spite of new catalysts emergence, process with aluminum chloride stays actual for many cumene producers. It is necessary to increase cumene production, because nowadays demand for cumene rose up to 12 million tons in 2011 and keeps growing.
1 .2 Reaction
The alkylation reaction of benzene with propylene is carried out in the presence of Lewis acids. It is known that alkylation occurs through activation of the olefin by catalyst, and then activated complex react s with benzene and alkylbenzenes.
Source: http://ac.els-cdn.com/S187661961400117X/1-s2.0-S187661961400117X-main.pdf?_tid=671789cc-a8b0-11e4-8ee1-00000aacb35e&acdnat=1422643812_65c2c345f702f7eeb47cc1e59aef483e
///////
TIP: Try the following search in ScienceDirect (www.sciencedirct.com) …
Elsevier ScienceDirect (www.sciencedirect.com) Advanced Search:
Journal Name: Procedia
Any field: Dibenzothiophene
Here are some of the results of the above search …
///////
Ionic Liquids: - The Novel Solvent for Removal of Dibenzothiophene from Liquid Fuel
Procedia Engineering, Volume 51, 2013, Pages 314-317
Composition of Initiated Cracking Products of High-sulfur Natural Bitumen
Procedia Chemistry, Volume 10, 2014, Pages 326-331
Deep Removal of Sulfur from Model Liquid Fuels using 1-Butyl-3-Methylimidazolium Chloride
Procedia Engineering, Volume 51, 2013, Pages 416-422
Sonocatalytic Oxidative Desulfurization of Thiophene and Its Derivatives
Procedia Engineering, Volume 42, 2012, Pages 1711-1719
Geochemistry of Aromatic Fractions in Es4 Oil Extracts from the South Slope of Dongying Sag and Its Implications
Procedia Environmental Sciences, Volume 11, Part B, 2011, Pages 680-685
The Biomarker Properties and Comparisons of Sahinali, Beypazarı and Karapınar (Turkey) Coaly Plio-Miocene Depositions
Energy Procedia, Volume 59, 2014, Pages 142-149
Heat Treatment Condition Influence on Novokuibyshevsk Vacuum Residue Component Composition
Procedia Chemistry, Volume 10, 2014, Pages 424-429
Recovery of Hazardous Metals from Spent Refinery Processing Solid Catalyst
Procedia Environmental Sciences, Volume 16, 2012, Pages 253-256
Enhanced Adsorption of Methyl Orange by Vermiculite Modified by Cetyltrimethylammonium Bromide (CTMAB)
Procedia Environmental Sciences, Volume 13, 2012, Pages 2179-2187
Air-Stable Anthracene-Phosphine Oxide Adduct Ligand in Pd Catalysed Suzuki-Miyaura Reactions
APCBEE Procedia, Volume 3, 2012, Pages 154-160
Biodegradation of Phthalate Esters by Variovorax sp
APCBEE Procedia, Volume 1, 2012, Pages 16-21
Analysis of Volatile Components from Dictyophora rubrovolota Zang, Ji Et Liou
Procedia Engineering, Volume 37, 2012, Pages 240-249
Cracking of Petroleum Residues by Reactive Molecular Distillation
Procedia Engineering, Volume 42, 2012, Pages 329-334
The Distribution of n-alkanes and polycyclic aromatic hydrocarbons in Water of Taihu Lake
Procedia Environmental Sciences, Volume 12, Part A, 2012, Pages 258-264
///////
Wednesday, October 23, 2013
What Do Patents & Hindawi Have in Common? They’re Both Free!
“Why can we
remember the tiniest detail that has happened to us, and not remember how many times we
have told it to the same person.” -- François de la Rochefoucauld (French
classical author, leading exponent of the Maxime, 1613-1680)
Two free full text desulfurization items of interest … a patent, and an article from the amazing Hindawi (http://www.hindawi.com/) open access journals database.
Details below …
///////
PATENT
Desulfurization of hydrocarbons by Ionic liquids and preparation of ionic liquids (Instituto Mexicano Del Petroleo)
Publication number
US20130118955 A1
Publication type
Application
Application number
US 13/733,173
Publication date
May 16, 2013
DE102009022284A1, US20090288992
Inventors
Natalya Victorovna Likhanova, Rafael Martinez Palou, Jorge Froylan Palomeque Santiago
Original Assignee
Instituto Mexicano Del Petroleo
Abstract
The present invention relates to an improved desulfurization process using an ionic liquid compound of general formula C+A−, where C+ represents an organic cation such as alkyl-pyridinium, di-alkyl imidazolium and tri-alkyl imidazolium; and A− is an anion of halides of iron (III), such as, for example, FeCl4 −. The desulfurization process is also improved when producing the ionic liquid compound by heating the reactants using microwave energy. The ionic liquids can be used to desulfurize hydrocarbon mixtures by a liquid-liquid extraction.
FIELD OF THE INVENTION
This invention provides a process for the synthesis of ionic liquids which can be used for the efficient removal of sulfur compounds from hydrocarbon mixtures. The ionic liquids related are insoluble in hydrocarbons but are able to dissolve aliphatic and aromatic sulfur compounds. Thus, the ionic liquids can be used for removal of sulfur compounds by a liquid-liquid extraction process at room temperature and pressure. The invention is also directed to a process for extracting sulfur from a hydrocarbon liquid by contacting the hydrocarbon with the ionic liquid.
More preferably, this invention is related to the synthesis of ionic liquids with general formula C+A−, where C+ is an organic cation preferably but not exclusively alkyl pyridinium, dialkylimidazolium, and trialkylimidazolium, the anion A− is preferably halogen ferrate (III), particularly Cl*FeCl3 − and Br*FeCl3. The invention is also directed to the process for the extraction of sulfur-containing compounds, such as sulfur compound that are present in gasoline and Diesel as contaminant obtained in petroleum refining processes by contacting with the ionic liquids.
BACKGROUND OF THE INVENTION
The production of gasoline according with the new European Environmental Standards requires that the refiners to lower the sulfur content in gasoline to values that are lower than 50 ppm since 2005. For example in Germany he content of sulfur in gasoline should be lower than 10 ppm. For the case of USA the content of sulfur is limited to lowest than 80 ppm and with average of 30 ppm. In attention to this claims, PEMEX Refining should be produce gasoline with sulfur content between 15 and 30 ppm for the years 2008-2010.
The classic method used for sulfur removal in Refining Processes is the catalytic Hydrodesulfurization (HDS technology) at high temperature and pressure. This method is very costly process that required drastic operation conditions and it is inefficient to reduce aromatic sulfur compounds especially for Mexican heavy crude oil, so is more reasonable the use of alternative desulfurization process. For increasing the efficiency of HDS process some technology modification are required such as the addition of other catalytic bed, more efficient catalyst, higher temperature and pressures and to reduce LHSV to expense of few processing capacity.
New technologic lines have been develop on in several countries in order to resolve this problem (Zaczepinski, S. Exxon, Diesel Oil Deep Desulfurization (DODD) in Handbook of Petroleum Refining Processes, ed. R. A. Meyer, Mc Graw-Hill, NY, 1996, Ch. 8.7), i.e.: the absorption of sulfur compounds over solid absorbents, like IRVAD® process (U.S. Pat. No. 5,730,860, dated Mar. 24, 1998) from Black & Veatch Pritchard Inc.; the process S-Zorb® from Phillips Petroleum (http://www.eia.doe.gov/oiaf/servicerpt/ulsd/uls.html), the process Haldor Topsoe (EP 1057879, dated Dec. 6, 2000); and the liquid-liquid extraction with volatile organic solvents (Petrostar Refining, 217 National Meeting, American Chemical Society, Anaheim, Calif., Marzo, 1999). An original process is the oxidative desulfurization with different oxidant agents (Unipure Corp., NPRA Meeting No AM-01-10, Marzo 2001; Sulphco Corp, NPRA Meeting No AM-01-55, March 2001; BP Chemicals UK, Journal of Molecular Catalysis A: Chemical (1997) 397-403; UOP LLC, U.S. Pat. No. 6,171,478, dated Jan. 9, 2001; EXXON Research and Engineering Co., U.S. Pat. No. 5,910,440, dated Jun. 8, 1999; U.S. Patent Publication No. 2002/0035306 A1 with publication date of Mar. 21, 2002; U.S. Pat. No. 6,596,914 B2, dated Jul. 22, 2003; U.S. Pat. No. 6,406,616, dated Jun. 18, 2002 and U.S. Pat. No. 6,402,940 B1 dated Jun. 11, 2002; Fuel 82 (2003) 4015; Green Chemistry 5 (2003) 639). Recently the extraction of sulfur-containing compounds using liquid-liquid extraction employing ionic liquids have been welcome by scientific community.
Ionic liquids are known for more than 30 years, but their industrial applications began in the last 10 years (Rogers, R. D.; Seddon, K. R (Eds.), Ionic Liquids: Industrial Applications of Green Chemistry, ACS, Boston, 2002). They are applied as solvents and catalyst in alkylation reactions, polymerization and Diels-Alder cycloaddition. In addition they are employed in electrochemical processes, in supercritical CO2 extraction of aromatic compounds and sulfur compounds in hydrocarbon mixtures. One of the first publications mention the use of ionic liquids for the removal of mercaptans (WO 0234863, dated May 2, 2002). The patented method is based on the use of sodium hydroxide in combination with ionic liquids for the conversion of mercaptans to mercaptures, which were removed using ionic liquids. Peter Wassercheid and coworkers published several papers and patents between 2001 and 2005 about the use of ionic liquids for desulfurization of gasolines (Chem. Comun. (2001) 2494; WO 03037835, with publication date of 2003 May 8; U.S. Publication No. 2005/0010076 A1, published Jan. 13, 2005). In these works the authors employed ionic liquids with C+ being 1,3-dialkylimidazolium or tetralkylammonium, and A− being tetrachloroaluminates or methanesulfonates. By means of a process with several extractions (up to 8 extractions), high extraction of sulfur compounds were achieved using model gasolines. However these kinds of compounds are air and moisture sensitive and a polymerization reaction was observed during the extraction process. U.S. Patent Publication No. 2003/0085156 A1 published May 8, 2003 and U.S. Pat. No. 7,001,504, dated Feb. 21, 2006, also mention the use of ionic liquids, where C+ is an ammonium o fosfonium and quaternary, A− being tetrachloroaluminates for the extraction of sulfur from model gasoline. In the paper published in Energy & Fuels 18 (2004) 1862, the use of ionic liquids containing Copper chloride (I) anion with the same application, and in the papers Ind Eng. Chem. Res. 43 (2004) 614 and Ind. Eng. Chem. Res. 46 (2007) 5108-5112) several ionic liquids were evaluated for the extraction of sulfur and nitrogen-containing compounds. More recently, some papers (Energy & Fuels 20 (2006) 2083-2087; Green Chemistry 8 (2006) 70-77; Progress in chemistry 19 (2007) 1331-1344; Green Chemistry 10 (2008) 87-92) also report the use of IL for desulfurization processes. U.S. Patent Publication No. 2004/00445874 A1, published Mar. 11, 2004, discloses a procedure for desulfurization and denitrogenation of hydrocarbons fractions using a wide family of ionic liquids and alkylations agents with high efficiency in some cases.
SUMMARY OF THE INVENTION
The present invention is directed to the use of ionic liquids containing halogens of Fe (III) as an anion for these purposes, where these compounds presented very high efficiency for extracting sulfur-containing compounds from gasoline, turbosin, diesel and other petroleum fractions. Another important and novel aspect of the invention is the use of microwave irradiation for synthesizing the ionic liquids suitable for use as extracting agents (symmetric and non-symmetric compounds) with a corresponding shorter time and higher yields in the synthesis of these ionic liquids compared to the conventional methods of synthesis.
The invention is also directed to a process for extracting sulfur and sulfur compounds from a sulfur-containing hydrocarbon liquid by contacting the hydrocarbon liquid with an ionic liquid of the invention for sufficient time to extract the sulfur and sulfur-containing compounds, and thereafter recovering the hydrocarbon liquid.
The ionic liquids of the invention comprise a heterocyclic cation and an iron (III) halide. The heterocyclic cation is an imidazolium compound having at least one C1-C10 alkyl group or alkoxy group where the alkyl group and alkoxy group can be linear, branched, substituted or unsubstituted. The heterocyclic cation can be symmetrical or asymmetrical.
Free Full Text Source: http://www.google.com/patents/US20130118955
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International Journal of Chemical Engineering, Volume 2013, Article ID 951045, 10 pages, http://dx.doi.org/10.1155/2013/951045
Investigation of Influential Parameters in Deep Oxidative Desulfurization of Dibenzothiophene with Hydrogen Peroxide and Formic Acid
Alireza Haghighat Mamaghani, Shohreh Fatemi, andMehrdad Asgari
shfatemi@ut.ac.ir
School of Chemical Engineering, College of Engineering, University of Tehran, Enghelab Avenue, P.O. Box 11155-4563, Tehran 11155-4563, Iran
Abstract
An effective oxidative system consisting of hydrogen peroxide, formic acid, and sulfuric acid followed by an extractive stage were implemented to remove dibenzothiophene in the simulated fuel oil. The results revealed such a great performance in the case of H2O2 in the presence of formic and sulfuric acids that led to the removal of sulfur compounds. Sulfuric acid was employed to increase the acidity of media as well as catalytic activity together with formic acid. The oxidation reaction was followed by a liquid-liquid extraction stage using acetonitrile as a polar solvent to remove produced sulfones from the model fuel. The impact of operating parameters including the molar ratio of formic acid to sulfur (nF/nS), hydrogen peroxide to sulfur (nO/nS), and the time of reaction was investigated using Box-Behnken experimental design for oxidation of the model fuel. A significant quadratic model was introduced for the sulfur removal as a function of effective parameters by the statistic analysis.
Using hydrogen peroxide with an acid has been widely investigated by several researchers. However, to the best knowledge of the authors, there are few studies which are concerned with optimizing the process parameters. The objective of the present work is to develop an efficient system for oxidative desulfurization of model fuel. ODS of dibenzothiophene (DBT) in n-octane as simulated fuel was performed in the presence of H2O2, formic acid, and H2SO4 as the oxidation system. After the oxidation step, a twostep liquid-liquid extraction with acetonitrile was applied to remove the oxidated sulfur compounds from the model fuel. Influences of operating conditions including H2O2/S molar ratio, acid formic/S molar ratio, oxidation duration time, and mediumaciditywere examined.Theextraction step was carried out at the same conditions in all experiments. Box-Behnken experimental design was implemented as a kind of response surface methodology (RSM) to arrange the experiments and develop amodel to explain the relationships of sulfur removal and the studied parameters and finally optimize the operating conditions.
Free Full Text Source: http://www.hindawi.com/journals/ijce/2013/951045/abs/
Two free full text desulfurization items of interest … a patent, and an article from the amazing Hindawi (http://www.hindawi.com/) open access journals database.
Details below …
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PATENT
Desulfurization of hydrocarbons by Ionic liquids and preparation of ionic liquids (Instituto Mexicano Del Petroleo)
Publication number
US20130118955 A1
Publication type
Application
Application number
US 13/733,173
Publication date
May 16, 2013
DE102009022284A1, US20090288992
Inventors
Natalya Victorovna Likhanova, Rafael Martinez Palou, Jorge Froylan Palomeque Santiago
Original Assignee
Instituto Mexicano Del Petroleo
Abstract
The present invention relates to an improved desulfurization process using an ionic liquid compound of general formula C+A−, where C+ represents an organic cation such as alkyl-pyridinium, di-alkyl imidazolium and tri-alkyl imidazolium; and A− is an anion of halides of iron (III), such as, for example, FeCl4 −. The desulfurization process is also improved when producing the ionic liquid compound by heating the reactants using microwave energy. The ionic liquids can be used to desulfurize hydrocarbon mixtures by a liquid-liquid extraction.
FIELD OF THE INVENTION
This invention provides a process for the synthesis of ionic liquids which can be used for the efficient removal of sulfur compounds from hydrocarbon mixtures. The ionic liquids related are insoluble in hydrocarbons but are able to dissolve aliphatic and aromatic sulfur compounds. Thus, the ionic liquids can be used for removal of sulfur compounds by a liquid-liquid extraction process at room temperature and pressure. The invention is also directed to a process for extracting sulfur from a hydrocarbon liquid by contacting the hydrocarbon with the ionic liquid.
More preferably, this invention is related to the synthesis of ionic liquids with general formula C+A−, where C+ is an organic cation preferably but not exclusively alkyl pyridinium, dialkylimidazolium, and trialkylimidazolium, the anion A− is preferably halogen ferrate (III), particularly Cl*FeCl3 − and Br*FeCl3. The invention is also directed to the process for the extraction of sulfur-containing compounds, such as sulfur compound that are present in gasoline and Diesel as contaminant obtained in petroleum refining processes by contacting with the ionic liquids.
BACKGROUND OF THE INVENTION
The production of gasoline according with the new European Environmental Standards requires that the refiners to lower the sulfur content in gasoline to values that are lower than 50 ppm since 2005. For example in Germany he content of sulfur in gasoline should be lower than 10 ppm. For the case of USA the content of sulfur is limited to lowest than 80 ppm and with average of 30 ppm. In attention to this claims, PEMEX Refining should be produce gasoline with sulfur content between 15 and 30 ppm for the years 2008-2010.
The classic method used for sulfur removal in Refining Processes is the catalytic Hydrodesulfurization (HDS technology) at high temperature and pressure. This method is very costly process that required drastic operation conditions and it is inefficient to reduce aromatic sulfur compounds especially for Mexican heavy crude oil, so is more reasonable the use of alternative desulfurization process. For increasing the efficiency of HDS process some technology modification are required such as the addition of other catalytic bed, more efficient catalyst, higher temperature and pressures and to reduce LHSV to expense of few processing capacity.
New technologic lines have been develop on in several countries in order to resolve this problem (Zaczepinski, S. Exxon, Diesel Oil Deep Desulfurization (DODD) in Handbook of Petroleum Refining Processes, ed. R. A. Meyer, Mc Graw-Hill, NY, 1996, Ch. 8.7), i.e.: the absorption of sulfur compounds over solid absorbents, like IRVAD® process (U.S. Pat. No. 5,730,860, dated Mar. 24, 1998) from Black & Veatch Pritchard Inc.; the process S-Zorb® from Phillips Petroleum (http://www.eia.doe.gov/oiaf/servicerpt/ulsd/uls.html), the process Haldor Topsoe (EP 1057879, dated Dec. 6, 2000); and the liquid-liquid extraction with volatile organic solvents (Petrostar Refining, 217 National Meeting, American Chemical Society, Anaheim, Calif., Marzo, 1999). An original process is the oxidative desulfurization with different oxidant agents (Unipure Corp., NPRA Meeting No AM-01-10, Marzo 2001; Sulphco Corp, NPRA Meeting No AM-01-55, March 2001; BP Chemicals UK, Journal of Molecular Catalysis A: Chemical (1997) 397-403; UOP LLC, U.S. Pat. No. 6,171,478, dated Jan. 9, 2001; EXXON Research and Engineering Co., U.S. Pat. No. 5,910,440, dated Jun. 8, 1999; U.S. Patent Publication No. 2002/0035306 A1 with publication date of Mar. 21, 2002; U.S. Pat. No. 6,596,914 B2, dated Jul. 22, 2003; U.S. Pat. No. 6,406,616, dated Jun. 18, 2002 and U.S. Pat. No. 6,402,940 B1 dated Jun. 11, 2002; Fuel 82 (2003) 4015; Green Chemistry 5 (2003) 639). Recently the extraction of sulfur-containing compounds using liquid-liquid extraction employing ionic liquids have been welcome by scientific community.
Ionic liquids are known for more than 30 years, but their industrial applications began in the last 10 years (Rogers, R. D.; Seddon, K. R (Eds.), Ionic Liquids: Industrial Applications of Green Chemistry, ACS, Boston, 2002). They are applied as solvents and catalyst in alkylation reactions, polymerization and Diels-Alder cycloaddition. In addition they are employed in electrochemical processes, in supercritical CO2 extraction of aromatic compounds and sulfur compounds in hydrocarbon mixtures. One of the first publications mention the use of ionic liquids for the removal of mercaptans (WO 0234863, dated May 2, 2002). The patented method is based on the use of sodium hydroxide in combination with ionic liquids for the conversion of mercaptans to mercaptures, which were removed using ionic liquids. Peter Wassercheid and coworkers published several papers and patents between 2001 and 2005 about the use of ionic liquids for desulfurization of gasolines (Chem. Comun. (2001) 2494; WO 03037835, with publication date of 2003 May 8; U.S. Publication No. 2005/0010076 A1, published Jan. 13, 2005). In these works the authors employed ionic liquids with C+ being 1,3-dialkylimidazolium or tetralkylammonium, and A− being tetrachloroaluminates or methanesulfonates. By means of a process with several extractions (up to 8 extractions), high extraction of sulfur compounds were achieved using model gasolines. However these kinds of compounds are air and moisture sensitive and a polymerization reaction was observed during the extraction process. U.S. Patent Publication No. 2003/0085156 A1 published May 8, 2003 and U.S. Pat. No. 7,001,504, dated Feb. 21, 2006, also mention the use of ionic liquids, where C+ is an ammonium o fosfonium and quaternary, A− being tetrachloroaluminates for the extraction of sulfur from model gasoline. In the paper published in Energy & Fuels 18 (2004) 1862, the use of ionic liquids containing Copper chloride (I) anion with the same application, and in the papers Ind Eng. Chem. Res. 43 (2004) 614 and Ind. Eng. Chem. Res. 46 (2007) 5108-5112) several ionic liquids were evaluated for the extraction of sulfur and nitrogen-containing compounds. More recently, some papers (Energy & Fuels 20 (2006) 2083-2087; Green Chemistry 8 (2006) 70-77; Progress in chemistry 19 (2007) 1331-1344; Green Chemistry 10 (2008) 87-92) also report the use of IL for desulfurization processes. U.S. Patent Publication No. 2004/00445874 A1, published Mar. 11, 2004, discloses a procedure for desulfurization and denitrogenation of hydrocarbons fractions using a wide family of ionic liquids and alkylations agents with high efficiency in some cases.
SUMMARY OF THE INVENTION
The present invention is directed to the use of ionic liquids containing halogens of Fe (III) as an anion for these purposes, where these compounds presented very high efficiency for extracting sulfur-containing compounds from gasoline, turbosin, diesel and other petroleum fractions. Another important and novel aspect of the invention is the use of microwave irradiation for synthesizing the ionic liquids suitable for use as extracting agents (symmetric and non-symmetric compounds) with a corresponding shorter time and higher yields in the synthesis of these ionic liquids compared to the conventional methods of synthesis.
The invention is also directed to a process for extracting sulfur and sulfur compounds from a sulfur-containing hydrocarbon liquid by contacting the hydrocarbon liquid with an ionic liquid of the invention for sufficient time to extract the sulfur and sulfur-containing compounds, and thereafter recovering the hydrocarbon liquid.
The ionic liquids of the invention comprise a heterocyclic cation and an iron (III) halide. The heterocyclic cation is an imidazolium compound having at least one C1-C10 alkyl group or alkoxy group where the alkyl group and alkoxy group can be linear, branched, substituted or unsubstituted. The heterocyclic cation can be symmetrical or asymmetrical.
Free Full Text Source: http://www.google.com/patents/US20130118955
///////
International Journal of Chemical Engineering, Volume 2013, Article ID 951045, 10 pages, http://dx.doi.org/10.1155/2013/951045
Investigation of Influential Parameters in Deep Oxidative Desulfurization of Dibenzothiophene with Hydrogen Peroxide and Formic Acid
Alireza Haghighat Mamaghani, Shohreh Fatemi, andMehrdad Asgari
shfatemi@ut.ac.ir
School of Chemical Engineering, College of Engineering, University of Tehran, Enghelab Avenue, P.O. Box 11155-4563, Tehran 11155-4563, Iran
Abstract
An effective oxidative system consisting of hydrogen peroxide, formic acid, and sulfuric acid followed by an extractive stage were implemented to remove dibenzothiophene in the simulated fuel oil. The results revealed such a great performance in the case of H2O2 in the presence of formic and sulfuric acids that led to the removal of sulfur compounds. Sulfuric acid was employed to increase the acidity of media as well as catalytic activity together with formic acid. The oxidation reaction was followed by a liquid-liquid extraction stage using acetonitrile as a polar solvent to remove produced sulfones from the model fuel. The impact of operating parameters including the molar ratio of formic acid to sulfur (nF/nS), hydrogen peroxide to sulfur (nO/nS), and the time of reaction was investigated using Box-Behnken experimental design for oxidation of the model fuel. A significant quadratic model was introduced for the sulfur removal as a function of effective parameters by the statistic analysis.
Using hydrogen peroxide with an acid has been widely investigated by several researchers. However, to the best knowledge of the authors, there are few studies which are concerned with optimizing the process parameters. The objective of the present work is to develop an efficient system for oxidative desulfurization of model fuel. ODS of dibenzothiophene (DBT) in n-octane as simulated fuel was performed in the presence of H2O2, formic acid, and H2SO4 as the oxidation system. After the oxidation step, a twostep liquid-liquid extraction with acetonitrile was applied to remove the oxidated sulfur compounds from the model fuel. Influences of operating conditions including H2O2/S molar ratio, acid formic/S molar ratio, oxidation duration time, and mediumaciditywere examined.Theextraction step was carried out at the same conditions in all experiments. Box-Behnken experimental design was implemented as a kind of response surface methodology (RSM) to arrange the experiments and develop amodel to explain the relationships of sulfur removal and the studied parameters and finally optimize the operating conditions.
Free Full Text Source: http://www.hindawi.com/journals/ijce/2013/951045/abs/
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